It is known from WO Publication No. 2015/185423 how to form a timepiece component from a part comprising a silicon-based or ceramic-based material which is welded by electromagnetic radiation directly onto another part, such as, for example, a metal or a metal alloy.
In the context of this development, it transpired that it was important for the gap between the parts not to exceed 0.5 micrometres, otherwise they could not be welded together.